I haven't had to find your dead relay yet, but when mine goes I'll be using this solid-state opto-isolated one. Current handling jumps from 30 to 50A @ 480VAC (on this model), with no contact arcing, because there is none. The "coil" is basically an LED that draws around 10-20ma.
I used to have a spa that used several exotic German relays that were really hard to find and really expensive when you could. I finally gave up and tried these SSR's and my relay problem vanished.
Just something to think about.. Other than expense, I don't know why they're not used more often.
Jeff - WA6EQU
'06 Itasca Meridian 34H, CAT C7/350